A. The birth parents, and the parents by previous adoption, if any, other than any such parent who is the husband or wife of one of the petitioners, shall, by final order of adoption, be divested of all legal rights and obligations in respect to the child including the right to petition any court for visitation with the child. Except where a final order of adoption is entered pursuant to § 63.2-1241, any person whose interest in the child derives from or through the birth parent or previous adoptive parent, including but not limited to grandparents, stepparents, former stepparents, blood relatives, and family members, shall, by final order of adoption, be divested of all legal rights and obligations in respect to the child including the right to petition any court for visitation with the child. In all cases the child shall be free from all legal obligations of obedience and maintenance in respect to such persons divested of legal rights. Any child adopted under the provisions of this chapter shall, from and after the entry of the interlocutory order or from and after the entry of the final order where no such interlocutory order is entered, be, to all intents and purposes, the child of the person or persons so adopting him and, unless and until such interlocutory order or final order is subsequently revoked, shall be entitled to all the rights and privileges, and subject to all the obligations, of a child of such person or persons born in lawful wedlock. An adopted person is the child of an adopting parent, and as such, the adopting parent shall be entitled to testify in all cases civil and criminal, as if the adopted child was born of the adopting parent in lawful wedlock.